Pneumatic systems are now widely used for out-of-doors or so-called "drive-up" banking in which tellers at indoors teller terminals attend to customers who motor up to out-of-doors customer terminals to do their banking. Typically, these systems employ carriers to transfer money and papers back and forth between the teller and customer terminals, which carriers are driven or drawn by pneumatic pressure through transit tubes interconnecting the terminals. Characteristic of these systems are the large radiused bends in the transit tubes, necessary in order to bring the tubes into the terminals (or otherwise to change their direction) and at the same time to allow the bends to be negotiated by the carriers.
One development in indoors banking is to confine the currency and the tellers in one area and the customers in another area, walled off from the first, so that there is no face to face contact between the two. The areas are then interconnected by some sort of communicating system transferring currency and papers between the two. This allows one teller to handle several customers at a time as well as provides additional security. Similar systems may be used for "personal bankers", those who sit at individual desks and handle more than routine transactions. Each may have a "customer" terminal at his desk so that cash or other valuables, instead of kept at his desk, remain in the "back room", as it were, until needed.
But use of the typical out-of-doors pneumatic system indoors is defeated by the large radiused tube bends required for the former which make the same prohibitedly costly and awkward in terms of installation space indoors. For practical reasons therefore it is necessary that pneumatic carriers for indoors banking be able to turn, as it were, "square corners". And that in turn requires some kind of transfer arrangement so that the carrier in a typical installation can move both vertically within each terminal and then immediately horizontally through a transit tube beneath the floor which joins the terminal bases at a right or similarly abrupt angle. So far as known, the most pertinent pneumatic systems of this nature are those in U.S. Pat. Nos. 3,419,229; 3,761,039; and 4,084,769. The first of these employs a blower at each end of the transit tube between the terminals and relies wholly upon an opening to the atmosphere at the upper end of the receiving terminal to create a vertical draft, owing to the escaping confluence of the blowers from the transit tube, which both halts the carrier at the receiving terminal and then elevates it in that terminal. This scheme is probably rather uncertain in operation and likely needs some added assistance to halt the carrier in alignment with the receiving terminal and then to elevate it initially (see, for example, U.S. Pat. Nos. 3,512,735 and 3,556,437 to these ends). The other two patents, 3,761,039 and 4,084,769, incorporate elevators which transport the carrier vertically in each terminal before and after its passage through the horizontal transit tube. These latter two arrangements, though assuring location of the carrier with respect to the terminals, tend to lack sufficient lifting ability owing to their use of a single blower and its relatively remote location. This is certainly the case when the carrier is heavily laden unless an out-sized and thus costly blower is used. Hence the chief object of the present invention is an indoors pneumatic system for banking and the like which avoids the foregoing deficiencies and vagaries of the prior art systems as well as incorporates additional novel features which enhance its operation.